Additive for liquid hydrocarbon fuel fueled in fired burners or open flames

ABSTRACT

A fuel additive for hydrocarbon fuel that is fueled in fired burners and open flames for enhancing fuel storage, for enhancing fuel combustion by increasing fuel efficiency, and/or for reducing undesirable emissions, such as pollutants, includes an inorganic metal oxide, a metal carboxylate, an acid, and an organic dispersion fluid.

TECHNICAL FIELD OF THE INVENTION

The present invention relates to the field of fuel additives, in particular, to an additive for hydrocarbon fuel fueled in fired burners and open flames to enhance storage, combustion by increasing fuel efficiency, and/or reduce undesirable emissions, such as pollutants.

BACKGROUND OF THE INVENTION

Many hydrocarbon fuels have been used, each with their own advantages and drawbacks. Examples of such fuels include diesel, kerosene, coke, fuel oil, heavy distillates and bunker fuels. Chemical compounds have been used as combustion improvers to enhance combustion efficiency, of these types of fuels. Many of these additives contain metallic elements such as manganese, iron, copper, cerium, calcium and barium. Each of these elements has advantages and disadvantages in particular applications. Drawbacks of certain iron compounds include limited solubility in fuels, toxicity, and expense as an additive. Interaction with sulfur and creation of sulfide precipitate may also occur, which is undesirable.

In addition to the goal of improved combustion efficiency, smoke emissions reduction is also a concern, particularly for heavier fuels in direct fired applications. The industry has not made substantial progress on development of a fuel additive for reducing smoke and particulate emissions in these applications.

A fuel additive that includes a combustion catalyst to reduce smoke and particulate emissions from open flame burners and other direct-fired applications would be advantageous. A fuel additive that increases efficiency and/or decreases pollutants for diesel and heavier fuels used in these applications would be particularly advantageous. It would also be advantageous to reduce smoke, particulate and nitrogen emissions from fuel applications. In addition to reduction of NOx, reduction or elimination of HCN emissions is highly desirable.

An additive that does not result in the formation of precipitates and burns clean during the combustion process would be desirable.

SUMMARY OF THE INVENTION

The present invention includes a fuel additive composition, an enhanced liquid hydrocarbon fuel, and a process of using the fuel additive in relation to liquid hydrocarbon fuel.

The fuel additive of the invention includes an organic metal oxide, a metal carboxylate, an acid, and an organic dispersion fluid.

The process of the invention consists of the steps of combining a fuel additive in an amount effective in the liquid hydrocarbon fuel to enhance fuel performance to the direct fired burner or open flame, and combusting said liquid hydrocarbon fuel with the fuel additive. The fuel additive includes an organic metal oxide; a metal carboxylate, an acid, and a organic dispersion fluid.

The enhanced liquid hydrocarbon fuel of the invention includes a substancial amount of liquid hydrocarbon fuel suitable for combustion in a fired burner or open flame; and an amount of fuel additive operable to enhance combustion that includes an organic metal oxide, a metal carboxylate, an acid, and an organic dispersion fluid.

DETAILED DESCRIPTION

The present invention is directed to fuel additive compositions and processes for improving combustion in fired burners and open flames, and substantially reducing potentially hazardous exhaust emissions. This invention is particularly adapted for reducing the percentages of hydrocarbons, carbon monoxide and molecular oxygen in fired burners and open flames exhaust emissions.

The term “hydrocarbon fuel” is employed herein to describe fuels in which carbon is the principal constituent and is intended to cover both powdered fuels such as coal and petroleum fuels oils which are primarily hydrocarbons.

The term “liquid hydrocarbon fuel” is intended to include combustible pills which are liquid or are capable of being liquefied when preheated. Thus, many of the residual oils are semi-solid in nature and are heated to temperatures of around 82.22° C. (180° F.) in order to increase their fluidity before they are used as burning fuels in fired burners and open flames. It will be understood that the term “liquid hydrocarbon fuel” includes these semi-solid types of residual oils as well as the liquid types of fuel oils.

While the invention is not limited to any theory, it is believed that the combined action of the active ingredients of the fuel additive composition in some way interferes with or alters the formation of sulfates of a type which would ordinarily produce adherent slag deposits. That the result is due to a combined or synergistic effect of the active components is indicated by the fact that neither metal oxide alone nor organic dispersion fluid alone nor acid alone nor metal soap alone will produce the desired result.

The invention is especially advantage in improving the storage and transportation of the liquid hydrocarbon fuel by avoiding the slag deposits (improve the pre-flame condition of the liquid hydrocarbon fuel), also improves the combustion of liquid hydrocarbon fuel in fired burners and open flames by reducing the drop size during the spray of the liquid hydrocarbon fuel (improve the flame condition of the liquid hydrocarbon fuel), and substantially reducing potentially hazardous exhaust emissions (improve the post-flame condition of the liquid hydrocarbon fuel).

The practice of the invention also reduces adherent acidic deposits, and provides a neutralizing action in the devices of the fired burners and open flames, therefore the corrosion is reduced. The compositions employed in the practice of the invention are readily prepared in a form in which they can be fed to the combustion chamber or the fuel while maintaining freedom from feeding difficulties in chemical vats, pumps, distribution lines and in fired burners and open flames.

The fuel additive composition of the present invention is formulated by combining a variety of inorganic metal oxides and organic components. With respect to the inorganic metal oxides, the composition contains at least one metal oxide selected from the group consisting of magnesium oxide, iron oxide, copper oxide, cobalt oxide, ruthenium oxide, osmium oxide and palladium oxide, and combinations of the same, in a preferred embodiment, the metal oxide is magnesium oxide. For preferred compositions, the total amount of inorganic metal oxides utilized generally ranges from about 30% to about 40% by weight, and more preferably from about 33% to about 38% by weight.

In an embodiment of the present invention, the inorganic metal oxide is added or mixed with an organic dispersion fluid. The organic dispersion fluid is a fluid that is operable to maintain the metal oxides within the dispersion fluid in at least a partially dispersed state and that is miscible, or capable of being maintained in solution, in the hydrocarbon fuel. The organic dispersion fluid may be selected from the group of hydrocarbons, gasoline, polygas, kerosene, diesel, mineral oil, benzene, toluene, xylene, aromatic oils, polybutenes, polyglycols, heavier oils, naphtha, naphthalene, and combinations thereof. In a preferred embodiment, the organic dispersion fluid is naphtha. For preferred compositions, the total amount of organic dispersion fluid utilized generally ranges from about 10% to about 20% by weight, and more preferably from about 13% to about 17% by weight.

The fuel additive composition of the present invention is neutralized by the addition of an acid that will substantially produce no water as a by-product. Typical acids include ammonium chloride, which is preferred, as well as ammonium salts of other common inorganic acids such as phosphoric, sulfuric and the like as well as organic acids such as acetic, citric and the like. For preferred compositions, the total amount of acid utilized generally ranges from about 1% to about 10 by weight, and more preferably from about 3% to about 7% by weight.

The fuel additive composition of the present invention includes a suitable stabilizer such as metal carboxylates. Particularly suitable metal carboxylates include, but are not limited to manganese octoate, cobalt octoate, zirconium octoate, calcium octoate and mixtures thereof. For preferred compositions, the total amount of metal carboxylate utilized generally ranges from about 10% to about 20% by weight, and more preferably from about 13% to about 17% by weight.

EXAMPLES

A fuel additive composition is prepared by combining 35% by weight of magnesium oxide, 15% by weight of calcium octoate, 5% by weight of ammonium chloride, and 15% by weight of naphtha.

Control Example

A sample of coke without fuel additive was calcined in a muffle furnace to a temperature of 900° C. (1,652° F.). Table 1 shows the content percent of the ash and the ash composition.

TABLE 1 Element Result (% P) Test method Ash 0.79 ASTM D-482 Ash composition Aluminium oxide <0.45 Atomic absorption spectroscopy Calcium oxide 9.10 Atomic absorption spectroscopy Iron oxide 2.60 Atomic absorption spectroscopy Magnesoum oxide 30.40 Atomic absorption spectroscopy Potassium oxide 0.44 Atomic absorption spectroscopy Sodium oxide 2.70 Atomic absorption spectroscopy Silicon dioxide 11.25 Gavimetric analysis Vanadium pentoxide 41.70 Atomic absorption spectroscopy Phosphates <0.05 Spectrophotometry Sulfates 1.60 Gavimetric analysis

Example 2

Use of 0.1% by weigth of the fuel additive composition described above in combination with coke. This combination of coke and fuel additive was calcined in a muffle furnace to a temperature of 900° C. (1,652° F.). Table 2 shows the content percent of the ash and the ash composition.

TABLE 2 Element Result (% P) Test method Ash 5.83 ASTM D-482 Ash composition Aluminium oxide <0.4 Atomic absorption spectroscopy Calcium oxide 3.6 Atomic absorption spectroscopy Iron oxide 0.6 Atomic absorption spectroscopy Magnesoum oxide 74.7 Atomic absorption spectroscopy Potassium oxide 0.12 Atomic absorption spectroscopy Sodium oxide 0.27 Atomic absorption spectroscopy Silicon dioxide <2.0 Gavimetric analysis Vanadium pentoxide 5.16 Atomic absorption spectroscopy Phosphates <0.05 Spectrophotometry Sulfates 15.0 Gavimetric analysis

Example 3

Use of 0.15% by weigth of the fuel additive composition described above in combination with coke. This combination of coke and fuel additive was calcined in a muffle furnace to a temperature of 900° C. (1,652° F.). Table 3 shows the content percent of the ash and the ash composition.

TABLE 3 Element Result (% P) Test method Ash 3.98 ASTM D-482 Ash composition Aluminium oxide <0.4 Atomic absorption spectroscopy Calcium oxide 4.38 Atomic absorption spectroscopy Iron oxide 0.98 Atomic absorption spectroscopy Magnesoum oxide 78.9 Atomic absorption spectroscopy Potassium oxide 0.06 Atomic absorption spectroscopy Sodium oxide 0.37 Atomic absorption spectroscopy Silicon dioxide <2.0 Gavimetric analysis Vanadium pentoxide 7.70 Atomic absorption spectroscopy Phosphates <0.05 Spectrophotometry Sulfates 7.70 Gavimetric analysis

Example 4

Use of 0.20% by weigth of the fuel additive composition described above in combination with coke. This combination of coke and fuel additive was calcined in a muffle furnace to a temperature of 900° C. (1,652° F.). Table 4 shows the content percent of the ash and the ash composition.

TABLE 4 Element Result (% P) Test method Ash 7.19 ASTM D-482 Ash composition Aluminium oxide <0.4 Atomic absorption spectroscopy Calcium oxide 3.67 Atomic absorption spectroscopy Iron oxide 0.57 Atomic absorption spectroscopy Magnesoum oxide 91.90 Atomic absorption spectroscopy Potassium oxide 0.05 Atomic absorption spectroscopy Sodium oxide 0.19 Atomic absorption spectroscopy Silicon dioxide <2.0 Gavimetric analysis Vanadium pentoxide 3.50 Atomic absorption spectroscopy Phosphates <0.05 Spectrophotometry Sulfates <0.50 Gavimetric analysis

Example 5

Use of 0.05% by weigth of the fuel additive composition described above in combination with coke. This combination of coke and fuel additive was calcined in a muffle furnace to a temperature of 900° C. (1,652° F.). Table 5 shows the content percent of the ash and the ash composition.

TABLE 5 Element Result (% P) Test method Ash 2.74 ASTM D-482 Ash composition Aluminium oxide <0.4 Atomic absorption spectroscopy Calcium oxide 3.1 Atomic absorption spectroscopy Iron oxide 0.4 Atomic absorption spectroscopy Magnesoum oxide 71.1 Atomic absorption spectroscopy Potassium oxide 0.14 Atomic absorption spectroscopy Sodium oxide 0.21 Atomic absorption spectroscopy Silicon dioxide <2.0 Gavimetric analysis Vanadium pentoxide 4.8 Atomic absorption spectroscopy Phosphates <0.05 Spectrophotometry Sulfates 19.1 Gavimetric analysis

Example 6

Use of 0.25% by weigth of the fuel additive composition described above in combination with coke. This combination of coke and fuel additive was calcined in a muffle furnace to a temperature of 900° C. (1,652° F.). Table 6 shows the content percent of the ash and the ash composition.

TABLE 5 Element Result (% P) Test method Ash 8.15 ASTM D-482 Ash composition Aluminium oxide <0.4 Atomic absorption spectroscopy Calcium oxide 3.7 Atomic absorption spectroscopy Iron oxide 0.61 Atomic absorption spectroscopy Magnesoum oxide 93.9 Atomic absorption spectroscopy Potassium oxide 0.06 Atomic absorption spectroscopy Sodium oxide 0.21 Atomic absorption spectroscopy Silicon dioxide <2.0 Gavimetric analysis Vanadium pentoxide 4.0 Atomic absorption spectroscopy Phosphates <0.05 Spectrophotometry Sulfates <0.5 Gavimetric analysis

In this manner, a reduction of vanadium peroxide (V₂O₅) occurs and at the same time, the catalytic conversion of SO₂ to SO₃ is also expected to inhibit the formation of the highest oxidation level of vanadium; vanadium pentoxide. This reduction of vanadium pentoxide further reduces associated ash problems.

Although the present invention has been described by way of particular embodiments and examples thereof, it should be noted that it will be apparent to persons skilled in the art that modifications may be applied to the present particular embodiment without departing from the scope of the present invention. 

1. A fuel additive composition for liquid hydrocarbon fuel fueled in fired burners or open flames comprising: an inorganic metal oxide; a metal carboxylate; an acid; and an organic dispersion fluid.
 2. The fuel additive composition of the claim 1, wherein comprises from 30% to 40% by weight of said inorganic metal oxide, preferably form 33% to 38% by weight of said inorganic metal oxide.
 3. The fuel additive composition of the claim 1, wherein comprises from 10% to 20% by weight of said metal carboxylate, preferably from 13% to 17% by weight of said metal carboxylate.
 4. The fuel additive composition of the claim 1, wherein comprises from 1% to 10% by weight of said add, preferably from 3% to 7% by weight of said add.
 5. The fuel additive composition of the claim 1, wherein comprises from 10% to 20% by weight of said organic dispersion fluid, preferably from 13% to 17% by weight of said organic dispersion fluid,
 6. The fuel additive composition of the claim 1, wherein said inorganic metal oxide is selected from a group consisting of magnesium oxide, iron oxide, copper oxide, cobalt oxide, ruthenium oxide, osmium oxide, palladium oxide, and combinations thereof.
 7. The fuel additive composition of the claim 6, wherein said inorganic metal oxide is magnesium oxide.
 8. The fuel additive composition of the claim 1, wherein said metal carboxylate is selected from a group consisting of manganese octoate, cobalt octoate, zirconium octoate, calcium octoate, and combinations thereof.
 9. The fuel additive composition of the claim 8, wherein said metal carboxylate is calcium octoate.
 10. The fuel additive composition of the claim 1, wherein said acid is selected from a group consisting of ammonium salts of inorganic and organic acids, and and combinations thereof.
 11. The fuel additive composition of the claim 10, wherein said acid is ammonium chloride.
 12. The fuel additive composition of the claim 1, wherein said organic dispersion fluid is selected from a group consisting of hydrocarbons, gasoline, polygas, kerosene, diesel, mineral oil, benzene, toluene, xylene, aromatic oils, polybutenes, polyglycols, heavier oils, naphtha, naphthalene, and combinations thereof.
 13. The additive composition of the claim 12, wherein said organic dispersion fluid is naphtha.
 14. A process to enhancing fuel performance of a liquid hydrocarbon fuel fueled in a combustion system having a direct fired burner or open flame comprising the steps of: combining a fuel additive in an effective amount in the liquid hydrocarbon fuel to enhance fuel performance to the direct fired burner or open flame; and combusting the said liquid hydrocarbon fuel with the fuel additive; wherein the fuel additive comprising: an inorganic metal oxide; a metal carboxylate; an acid; and an organic dispersion fluid.
 15. The process of the claim 14, wherein comprises from 30% to 40% by weight of said inorganic metal oxide, preferably from 33% to 38% by weight of said inorganic metal oxide.
 16. The process of the claim 14, wherein comprises from 10% to 20% by weight of said metal carboxylate, preferably from 13% to 17% by weight of said metal carboxylate.
 17. The process of the claim 14, wherein comprises from 1% to 10% by weight of said add, preferably from 3% to 7% by weight of said add.
 18. The process of the claim 14, wherein comprises from 10% to 20% by weight of said organic dispersion fluid, preferably from 13% to 17% by weight of said organic dispersion fluid.
 19. The process of the claim 14, wherein said inorganic metal oxide is selected from a group consisting of magnesium oxide, iron oxide, copper oxide, cobalt oxide, ruthenium oxide, osmium oxide, palladium oxide, and combinations thereof.
 20. The process of the claim 19, wherein said inorganic metal oxide is magnesium oxide.
 21. The process of the claim 14, wherein said metal carboxylate is selected from a group consisting of manganese octoate, cobalt octoate, zirconium octoate, calcium octoate, and combinations thereof.
 22. The process of the claim 21, wherein said metal carboxylate is calcium octoate.
 23. The process of the claim 14, wherein said acid is selected from a group consisting of ammonium salts of inorganic and organic acids, and and combinations thereof.
 24. The process of the claim 23, wherein said acid is ammonium chloride.
 25. The process of the claim 14, wherein said organic dispersion fluid is selected from a group consisting of hydrocarbons, gasoline, polygas, kerosene, diesel, mineral oil, benzene, toluene, xylene, aromatic oils, polybutenes, polyglycols, heavier oils, naphtha, naphthalene, and combinations thereof.
 26. The process of the claim 25, wherein said organic dispersion fluid is naphtha.
 27. An enhanced fuel comprising: a substancial amount of liquid hydrocarbon fuel suitable for combustion in a fired burner or open flame; and an amount of fuel additive of claim 1 operable to enhance combustion. 